diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 1765e014aa081eb2080ca5f488cd3829fd2f4325..b6ca898a65d0045d2c55f1356a89b4ba06824a3a 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -832,6 +832,7 @@ struct dwc3_hwparams { * @list: a list_head used for request queueing * @dep: struct dwc3_ep owning this request * @sg: pointer to first incomplete sg + * @start_sg: pointer to the sg which should be queued next * @num_pending_sgs: counter to pending sgs * @remaining: amount of data remaining * @epnum: endpoint number to which this request refers @@ -848,6 +849,7 @@ struct dwc3_request { struct list_head list; struct dwc3_ep *dep; struct scatterlist *sg; + struct scatterlist *start_sg; unsigned num_pending_sgs; unsigned remaining; diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 8796a5ee9bb95fe2e9e0b0455d3ae55614ca9bef..56ca1666b35fe8b20459a3a849597bddcb84924c 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -985,11 +985,19 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_request *req, unsigned chain, unsigned node) { struct dwc3_trb *trb; - unsigned length = req->request.length; + unsigned int length; + dma_addr_t dma; unsigned stream_id = req->request.stream_id; unsigned short_not_ok = req->request.short_not_ok; unsigned no_interrupt = req->request.no_interrupt; - dma_addr_t dma = req->request.dma; + + if (req->request.num_sgs > 0) { + length = sg_dma_len(req->start_sg); + dma = sg_dma_address(req->start_sg); + } else { + length = req->request.length; + dma = req->request.dma; + } trb = &dep->trb_pool[dep->trb_enqueue]; @@ -1055,7 +1063,7 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep) static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, struct dwc3_request *req) { - struct scatterlist *sg = req->sg; + struct scatterlist *sg = req->start_sg; struct scatterlist *s; int i; @@ -1088,6 +1096,16 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, dwc3_prepare_one_trb(dep, req, chain, i); } + /* + * There can be a situation where all sgs in sglist are not + * queued because of insufficient trb number. To handle this + * case, update start_sg to next sg to be queued, so that + * we have free trbs we can continue queuing from where we + * previously stopped + */ + if (chain) + req->start_sg = sg_next(s); + if (!dwc3_calc_trbs_left(dep)) break; } @@ -1178,6 +1196,7 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep) return; req->sg = req->request.sg; + req->start_sg = req->sg; req->num_pending_sgs = req->request.num_mapped_sgs; if (req->num_pending_sgs > 0)